In an unprecedented, precautionary crackdown, safety officials are ordering every sawmill in British Columbia to remove all accumulated sawdust from their premises, a factor cited as a possible trigger of two catastrophic mill explosions in the past three months.

The edict, issued last week by WorkSafeBC, comes after a devastating blast recently leveled the Lakeland Mills in Prince George, killing two workers. In January, a sawmill exploded in Burns Lake, claiming two victims.

Investigators are focusing on high levels of sawdust from the cutting of wood killed by pine beetles as a possible trigger.

Two WorkSafeBC inspection reports disclosed last week showed earlier concern over dust at the Lakeland Mills. One of the inspections took place in February, just two weeks after the Babine Forest Products Mill blew up in Burns Lake.